1. Field of the Invention
The present invention relates to a telecommunication system, and more particularly, a telecommunication device having a battery capacity recovery apparatus and method thereof.
2. Background of the Related Art
Generally, a wireless telephone, both cordless and mobile telephone, uses a radio link substituted for a cord typically used in landline telephones. A cordless telephone is appropriately used within a short-distance range, such as a room, and a mobile telephone is used within an intermediate or long distance range, especially when a user is at a remote location.
For such wireless telephones, one frequency or multiple frequencies may be used. As shown in FIG. 1A, if the telephone device is a cordless telephone, the handset communicates with a base unit, which includes a recharge receptacle and may include a keypad and a display, connected to a landline (dotted lines). Also, one or more handsets may be used for one base unit.
If the telephone device is a mobile telephone, the cell phone would communicate with a base station via a digital communication or an analog communication, and the base unit includes a recharge receptacle connected to an AC/DC converter. Further, one or more cellular phones would communicate with the base station.
In a conventional wireless telephone, the battery of the handset or the cellular telephone is temporarily used only when the user makes or receives a call. After the temporary use, the battery is rendered to be in a recharge state, if the telephone is placed in the recharge receptacle. Thus, discharge and recharge operations are repeatedly carried out for the battery.
FIG. 1A is a block diagram illustrating the configuration of a related art wireless telephone associated with a recharge device. In the related art wireless telephone, the base unit includes a constant voltage generating unit 1 incorporated in a recharge device.
The handset or the cellular phone includes (hereinafter, collectively referred to as handset unit) a recharge detecting unit 2 for detecting whether or not a handset unit is connected to the constant voltage generating unit 1 of the recharge device via recharge terminals, and a control unit 3 for determining whether or not the handset unit is connected to the recharge device, based on a detect signal outputted from the recharge detecting unit 2, and for controlling a recharge function of the handset unit based on the result of the determination, and a recharge current control resistor 4 is used to control a recharge current supplied to a battery 5 via the recharge terminals. The battery 5 is incorporated in the handset unit and recharged with a constant voltage supplied from the constant voltage generating unit 1.
Now, the charge operation of the related art wireless telephone having the above mentioned configuration will be described in detail. Where it is desired to recharge the battery 5 of the handset unit, the handset unit is first connected to the recharge terminals of the recharge device. In this state, the handset unit is connected to the constant voltage unit 1 of the recharge device, thereby causing a constant voltage to be supplied from the constant voltage unit 1 to the handset unit. A current is introduced into the battery 5 via the recharge current control resistor 4, thereby causing the battery 5 to be recharged with a constant voltage.
The recharge detecting unit 2 incorporated in the handset unit detects whether or not the handset unit is connected to the recharge device, and informs the control unit 3 of the detection result. When the control unit 3 determines, based on the information from the recharge detecting unit 2, that the handset unit is connected to the recharge device, it conducts a control for recharging the battery 5 with a constant voltage supplied from the constant voltage generating unit 1 of the recharge device.
However, the above mentioned related art wireless telephone has a problem associated with a xe2x80x9cmemory effectxe2x80x9d of the battery 5 generated due to the habitual use pattern of the user associated with the use of the handset unit. For example, the user typically uses the handset of the cordless telephone after taking up the handset unit from a state in which the handset is laid on the recharge device (that is, a recharge state) of the base unit. During the use, the handset is in a discharge state. After the use of the handset, the user puts the handset on the recharge device of the base unit. Due to such a habitual use pattern of the user associated with the use of the handset, a memory effect is involved in the battery 5.
Users who have a technical knowledge about a memory effect on batteries may reduce, to some degree, the problem associated with the memory effect by appropriately controlling the use pattern for wireless telephones. However, most users repeat discharge and recharge operations for a battery without discharging the battery to a deep discharge state. For this reason, the battery has a capacity portion substantially unused. This capacity portion is gradually inactivated, so that it cannot be used. As a result, the battery has a reduced capacity corresponding to the capacity portion subjected to discharge and recharge operations. That is, a memory effect is generated. A similar effect occurs for mobile telephones when a user repeatedly recharges the battery without fully depleting the battery.
This memory effect results in a considerable reduction in the standby time or use time of the handset unit. The degradation resulting from such a memory effect occurs more frequently, as compared to those resulting from other factors.
An object of the invention is to solve at least the above problems and/or disadvantages and to provide at least the advantages described hereinafter.
An object of the invention is to provide a battery capacity recovery apparatus and method for periodically conducting discharge and recharge operations for a battery used in a wireless telephone to prevent a memory effect on the battery, thereby being capable of reducing the battery degradation while maximizing the convenience of the user.
In accordance with one aspect, the present invention provides in a system including a recharge device for recharging a battery, and an operating device adapted to use a voltage supplied from the battery, a battery capacity recovery apparatus comprising: a control unit for controlling the system; a voltage detecting unit for measuring a voltage condition of the battery, and outputting a signal indicative of the measured voltage condition to the control unit; a recharge detecting unit connected to a constant voltage unit included in the recharge device, the recharge detecting unit serving to detect whether or not the operating device is connected to the recharge device; and a recovery path establishing unit adapted to establish a path for recovering the capacity of the battery under a control of the control unit.
In accordance with another aspect, the present invention provides in a system including a recharge device for recharging a battery, and an operating device adapted to use a voltage supplied from the battery, a battery capacity recovery method comprising the steps of: setting a reference voltage for the battery; connecting the operating device to the recharge device; detecting a voltage of the battery; determining whether or not an operation for recovering the capacity of the battery is to be executed; determining whether or not the detected battery voltage is not less than the reference voltage; and executing a recharge or discharge operation, based on the results of the determinations.
The battery capacity recovery apparatus and method can prevent a memory effect more frequently resulting in a battery degradation, as compared to those resulting from other factors. Accordingly, it is possible to reduce the battery degradation while maximizing the convenience of the user.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objects and advantages of the invention may be realized and attained as particularly pointed out in the appended claims.